Answer: 10
Explanation: 10 + 4.1 = 10
Symbol "X" represents Nitrogen, phosphorus, and arsenic.as they have five valence electrons in their valance shell.
<h3>What is a Lewis notation?</h3>
A Lewis form is a completely simplified illustration of the valence shell electrons in a molecule. it's miles used to expose how the electrons are organized round man or woman atoms in a molecule. Electrons are proven as dots or for bonding electrons as a line between the 2 atoms.
Lewis systems, also known as electron-dot structures or electron-dot diagrams, are diagrams that show the bonding between atoms of a molecule, and the lone pairs of electrons that can exist within the molecule.A Lewis form is based totally at the idea of the octet rule, wherein atoms percentage electrons in order that every atom has 8 electrons in its outer shell. for example, an oxygen atom has six electrons in its outer shell.
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Answer:
the last period. i think has the largest energy level
Explanation:
Acetylene is the only fuel gas suitable for gas welding because of its favourable flame characteristics of both high temperature and high propagation rates. Other fuel gases, such as propane, propylene or natural gas, produce insufficient heat input for welding but are used for cutting, torch brazing and soldering.
They are non-renewable resources that formed when prehistoric plants and animals died and were gradually buried by layers of rock.